^ ' 'l 



-4 



r 1 



6 



MISS B, M. BRISTOL ON 



from figs, 1, 14^ and 16 that variation may also occur in that the central part 

 and the radiating branches become very strongly developcJ, producing a 

 much more massive chloroplast, somewhat reminiscent oE that described tor 

 Chlorochytrhim (jrande. 



Pyrenoids are present in tlie cell, the number varying considerably in 

 different individuals. They are usually situated in the parietal portion o£ 

 the chromatophon*, often just at the junction of a radiating branch, though 

 in some cases they may bo nearer the centre o£ tlie cell. Starch is present 

 both in the starch-sheatlis of the pyrenoids and in the form of small scattered 

 granules. 



Of tlie other forms' very closely resembling 6\ Lemnce, C. Kmjanmn has 

 been recorded from Lenuta minor and ^ibha^ CeratopliyUum demersum^ and 

 Elodea canadensis. It ^vas first described, but not named, by Kny* in 1874 

 as an endophytic alga^ differing from C. Lemnir only in size and in the absence 

 of a cellulose button at the end of the tubular neck. Four years later 

 Szymanski t found a form which was apparently identical with tliat described 

 by Kny, but which possessed a cellulose button not protruding further than 

 twice the thickness of its outer wall above the epidermis of the host-plant. 

 Kirchner I recorded the species from Breslau in the same year, and Klebs §, 

 in 1881 5 added the inforjnation that only asexual zoogonidia were produced. 

 He further suggested that it bore such a very striking resemblance to 

 C. Lemnte that it was ])robably only an asexual form of the same species. 



The fourth species of this group, Chlorochjtrmm Archerianum^ was 

 established by Hieronymns |I in 1887^ though the alga had been described 



out>ht that it was most 



It 



If 



and figured earlier by Archer 



probably a stage in the life-history of Chlamydonujxa lahjrinthnloides. 

 was found in punctured cells of Si>lia(jmim^ and very closely resembles 

 C Leninai, with the difference that it is characterised at maturity by a 

 usually strongly developed cellulose button, and that its zoogonidia do not 



fuse* 



The separation of these four species is thus based on three characters : 

 the size of the cell, the degree of development of the cellulose button^ and 

 the fusion of tlie zoogonidia. A study of alga? belonging to this group, 

 extending over a period of more than two years, has convinced me that 



Kny, L, *' Ueber eine jji'iiae parnsitische Alge." Sitz. Gesellsch. naturf. Freuude zu 

 Berlin, 1874. 



t Szymauriki, F. '* Ueber einig-e parasitisclie Algen." Inaug.-dissert. derUniv. Breslau, 

 1878- 



X Kirchner. 'Die Algen Sclileslens,' 1878, 



§ Klebs, G. Bot. Zeit. xxxix. (1881) coL i>o5-257. 



li IliiU'onjmus. Jaliresber. Schles, Geselldch. 1887, p. 296. 

 1[ Archer, W. *' On Chlamydomyxa lahyriyithuhides^ nov. 

 vol. XV. p. 120, tab, 7. f. 1. 



gen." Quart, Jouni, Micr. Sci, 



